Firing line catcher



June 14, 1949. .1. D. WILLIAMS 2,472,997

FIRING LINE CATCHER Filed D90. 19, 1946 2 Sheets-Sheet 1 VV VV VV June 14, 1949. J. D. WILLIAMS 2,472,997

FIRING LINE CATCHER Filed Dec. 19. 1946 2 Sheds-Sheet 2 Patented June 14, 1949 UNlTED STATES PATENT OFFICE 2,472,997 FIRING LINE OATCHER JerryD. Williams, Chickaslia, Okla.

Application December 19, 1946, Serial No. 717,158

3 Claims.

This invention relates to a firing line catcher specially designed for use in exploration seismographic well shooting.

An object of the present invention is to provide a line catcher adapted to be lowered the required distance into a well 'bore and so designed that it will catch and entangle the firing line used in firing the explosive charge so that said firing line will not be liable to come into contact with a high tension electric power line to conduct an electrical current from said power line.

In exploration work, utilizing the seisomograpic method, it is common practice to drill bore holes into the earth sometimes to a depth of several hundred feet and to then place explosive charges at the bottom of the bore holes which, when fired, cause earth vibrations which are picked up at the surface by recording instruments.

The explosive charges are usually detonated by b means of electric caps placed therein before the charges are lowered. The cap of a charge is connected to two wires which, in turn, are connected to a battery or generating blaster and extend down the hole to the charge.

when a charge is detonated the mud, water and cap wires are blown out of the hole, said wires going into the air to their full length from the blaster or battery, and they often fall across or come into contact with high tension electric power lines thus endangering the members of the operating crew and destroying the recording instruments and the equipment connected with the firing lines as well as causing damage to power lines themselves. At times the firing lines blown out of the bores break and are carried by a much greater distance than their length and should they fall across a high tension electric power line they are a constant source of danger to persons and to live stock.

, It is desirable to drill these bore holes alon highways on public property for the reason that the drilling of them will not interfere with agricultural or grazing lands and heavy equipment employed will not have to be transported so far on of passable highways and in as much as high tension electrical power lines follow most hi hways it is desirable that means b provided for retaining the firing lines in or near the place the explosion occurs so that contact will not be made with the power lines.

The invention hereinafter described has been designed for the special purpose of limiting the range of travel of the firing line upon detonation of the: explosive charge at the bottom of the well bore.

It is another obiect of the present invention to provide a line catcher of very simple construction which may be located in the upper part of the bore having means thereon for entangling the 60 2 firing line, upon detonation of the explosive charge, and which will not interfere with the escape of the mud and water from the well, when the charge is fired, with means for retaining the catcher in or near the bore.

With the above and other objects in view the invention has particular relation to certain novel features of construction, arrangement of parts and use, an example of which is given in this specification and illustrated in the accompanying drawings, wherein:

Figure 1 is a side view of the catcher in the well illustrating one means of anchoring it and showing the explosive charge connected to the firing lines.

Figure 4 is a side view of th catcher in the well showing the explosive charge connected to the firing lines with a weight connected to the catcher for limiting and controlling its range of movement.

Referring now more particularly to the 'drawings wherein like numerals of reference designate the same parts in each of the figures, the numeral l designates a bar of any selected length and composed of any suitable material. It is preferably formed of rather heavy metal.

In the present illustration it is shown as being equipped with a suitable cross arm 2 and is extended above said arm and formed with an eye 3. The arm 2 rests on the ground surface and limits the distance the catcher is inserted in the well.

The bar I is provided with grapples, as 4. In the present illustration they are shown as downwardly directed hooks arranged about the bar and distributed longitudinally along the bar. Any desiderd number of these grapples may be employed and they may be of any selected formation to accomplish the purpose.

As illustrated in Figures 1, 2 and 3 there is an anchor chain whose ends are anchored to the ground surface by means of suitable stakes 6, 6 which are spaced apart and driven into the ground and to the upper ends of which the ends of the chain 5 are connected. For convenience the upper ends of the stakes may have eyes, as I, for attaching the ends of the chain thereto. Of course, instead of a chain, cable or other similaranchoring device may be employed.

The chain, or cable, is connected, at its midoint, to the eye 3 of the bar I by means of a suitable connecting member 8 such as a chain, or cable.

As an alternative means of anchoring the bar l, a weight 8 may be employed which may be connected to the upper end of the bar I by means of a chain or cable N. If this weight is employed it would be possible to' dispense with the cross arm 2 as the weight in itself would hold the bar suspended in the well bore.

This weight, if used, should be placed on the opposite side of the well bore from high tension electric lines.

The explosive charge is indicated by the numeral II. It is connected to the firing lines l2 and lowered into the bore to the bottom thereof. These firing lines are preferably passed through the eye 3 and continue on to a battery, blaster, or other source of electrical energy.

Preferably the firing lines are passed through an eye in the upper end of a stake I; which is driven into the ground near the well bore so that when the catcher is suddenly forced upwardly by the explosion the lines, or conductors, I! will be broken as is indicated in Figure 2.

Upon completion of a circuit through the conductors l2 the explosive charge II will be detonated and the contents of the bore, such as water or mud, along with the conductors l2 will be suddenly forced upwardly, as indicated in Figure 2, and the catcher will also be elevated but will be held against complete ejection from the bore by means of the chain, or cable, 5. The firing lines, or conductors, llwill become entangled with the grapples 4 and will be retained in the bore. Furthermore, the catcher itself will be kept under control and will not be ejected out and possible injuries thereby will thus be prevented.

Should the weight 8 be used, upon explosion of the charge, the firing line will become entangled on the hooks, or grapples, 4 as above explained and if the catcher is completely ejected from the bore its range of movement will be limited and it will fall over on the ground adjacent the bore and since the weight 8 is placed on the opposite side of the bore from an adjacent high tension line the catcher will fall in a direction away from said high tension line.

The drawings and description are illustrative merely while the broad principle of the invention will be defined by the appended claims.

What I claim is:

1. A safety device for use in bore hole blasting wherein firing lines are employed for detonation purposes, comprising a bar adapted to be inserted in an earth bore hole. downwardly directed hooks arranged about the bar and distributed longitudinally therealong and secured thereto, means connected to the bar and adapted to be anchored at the ground surface to limit the upward movement of the bar whereby upon insertion of the bar member in the bore hole said hooks are adapted to impede and entangle the firing lines in response to an explosive force in the bore beneath the bar.

2. A safety device for use in bore hole blasting wherein firing lines are employed for detonation purposes, comprising an elongated bar adapted to be inserted in the upper end of an earth bore, a transverse cross arm on the bar adapted to limit the downward movement of the bar in the bore, a flexible member connected to the bar and adapted to be anchored at the earth surface, and firing line engaging means distributed in spaced relation longitudinally along the bar and secured thereto and adapted to impede and entangle the firing lines in response to an explosive force in the bore beneath the bar.

3. A safety device for use in bore hole blastin wherein firing lines are employed for detonation purposes, comprising an elongated body adapted to be inserted in an earth bore, firing line engaging means distributed in space relation along the body and secured thereto, a transverse cross-arm on the body adapted to limit the downward movement of the body in the bore, a weight at the ground surface and a flexible member connecting the weight to the body for limiting the upward movement thereof whereby the firing line engaging means are adapted to impede and entangle the firing lines in response to an explosive force in the bore beneath the body.

JERRY D. WILLIAMS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

